Many functions of modern devices in automotive, consumer and industrial applications, such as converting electrical energy and driving an electric motor or an electric machine, rely on power semiconductor devices. For example, Insulated Gate Bipolar Transistors (IGBTs), Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) and diodes, to name a few, have been used for various applications including, but not limited to switches in power supplies and power converters.
A power semiconductor device usually comprises a semiconductor structure configured to conduct a load current along a load current path between two load terminal structures of the device. Further, the load current path may be controlled by means of a control electrode, sometimes referred to as gate electrode. For example, upon receiving a corresponding control signal from, e.g., a driver unit, the control electrode may set the power semiconductor device in one of a conducting state and a blocking state.
In Field Oriented Control (FOC) of a three-phase motor, the motor phase current needs to be measured. In order to reduce system cost, some applications use only one shunt resistor (i.e., a single shunt) placed on negative direct current (DC) link and then use software to re-construct the three-phase current. With a standard space vector pulse width modulation (SVPWM) scheme, if the on time (t_on) or off time (t_off) between two motor phases are too close (hereinafter “narrow pulse”), single shunt current sensing will not be able to sense the motor current correctly because there is not enough time for the two phases to stabilize. This limitation affects the motor control performance especially during motor start or at low running speeds.